Summary

This article discusses a hotfix that enables new logging functionality when DCOM errors occur in Microsoft COM+ applications. It also briefly discusses DCOM errors, the causes of DCOM errors, and how to troubleshoot DCOM errors.

Symptoms

When a DCOM error occurs, the error message does not contain sufficient information to determine the cause of the DCOM error. Instead, you may receive an error message that is similar to the following in Event Viewer:

Event Type: Error Event Source: DCOM Event ID: 10009 Description: DCOM was unable to communicate with the computerComputerName using any of the configured protocols.

Note In this error message, ComputerName is a placeholder for the name of the computer that is unavailable.

No other information is available in the error log. To locate more information about the error that occurred, you must typically debug the application or analyze the network traffic.

Resolution

A hotfix for this problem is now available from Microsoft. After you apply this hotfix, DCOM will log remote procedure call (RPC) extended error information in the event log to help determine the cause of the DCOM error.

Service pack information

To resolve this problem, obtain the latest service pack for Windows Server 2003. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

Hotfix rollup package information

This problem is fixed in Microsoft Windows Server 2003 Post-Service Pack 1 COM+ 1.5 Hotfix Rollup Package 7. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

Hotfix information

Prerequisites

Restart requirement

You must restart the computer after you modify the registry to enable this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

Registry information

You must modify the registry to enable this hotfix.

Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:

On the Edit menu, click Add Value, and then add the following registry value.

Value name

Data type

Value

Notes

EnableEELogging

REG_DWORD

1

This registry value enables or disables logging in text format. This format is appropriate for manual analysis of the logs.

LogEEInfoAsNative

REG_DWORD

1

This registry value enables or disables logging in Event Viewer. If you enable this kind of logging, you can use automated analysis to examine the extended error information.

Quit Registry Editor.

The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.

File information

Windows Server 2003, Itanium Architecture

File name

File version

File size

Date

Time

Platform

Service branch

Catsrv.dll

2001.12.4720.445

622,080

17-Nov-2005

02:45

IA-64

Not Applicable

Catsrvut.dll

2001.12.4720.445

1,555,456

17-Nov-2005

02:45

IA-64

Not Applicable

Clbcatex.dll

2001.12.4720.445

263,680

17-Nov-2005

02:45

IA-64

Not Applicable

Clbcatq.dll

2001.12.4720.445

1,287,168

17-Nov-2005

02:45

IA-64

Not Applicable

Colbact.dll

2001.12.4720.445

171,008

17-Nov-2005

02:45

IA-64

Not Applicable

Comadmin.dll

2001.12.4720.445

411,136

17-Nov-2005

02:45

IA-64

Not Applicable

Comrepl.dll

2001.12.4720.445

275,456

17-Nov-2005

02:45

IA-64

Not Applicable

Comsvcs.dll

2001.12.4720.445

3,143,168

17-Nov-2005

02:45

IA-64

Not Applicable

Comuid.dll

2001.12.4720.445

1,873,408

17-Nov-2005

02:45

IA-64

Not Applicable

Es.dll

2001.12.4720.445

654,336

17-Nov-2005

02:45

IA-64

Not Applicable

Msdtcprx.dll

2001.12.4720.445

1,311,744

17-Nov-2005

02:45

IA-64

Not Applicable

Msdtctm.dll

2001.12.4720.445

3,152,384

17-Nov-2005

02:45

IA-64

Not Applicable

Msdtcuiu.dll

2001.12.4720.445

463,360

17-Nov-2005

02:45

IA-64

Not Applicable

Mtxclu.dll

2001.12.4720.445

203,776

17-Nov-2005

02:45

IA-64

Not Applicable

Mtxdm.dll

2001.12.4720.445

45,568

17-Nov-2005

02:45

IA-64

Not Applicable

Mtxoci.dll

2001.12.4720.445

320,000

17-Nov-2005

02:45

IA-64

Not Applicable

Ole32.dll

5.2.3790.445

3,582,976

17-Nov-2005

02:45

IA-64

Not Applicable

Olecli32.dll

5.2.3790.445

223,744

17-Nov-2005

02:45

IA-64

Not Applicable

Olecnv32.dll

5.2.3790.445

89,088

17-Nov-2005

02:45

IA-64

Not Applicable

Rpcproxy.dll

5.2.3790.141

73,216

17-Nov-2005

02:45

IA-64

Not Applicable

Rpcrt4.dll

5.2.3790.141

2,150,400

17-Nov-2005

02:45

IA-64

Not Applicable

Rpcss.dll

5.2.3790.445

694,272

17-Nov-2005

02:45

IA-64

Not Applicable

Stclient.dll

2001.12.4720.445

140,800

17-Nov-2005

02:45

IA-64

Not Applicable

Txflog.dll

2001.12.4720.445

280,064

17-Nov-2005

02:45

IA-64

Not Applicable

Wcatsrv.dll

2001.12.4720.445

258,560

17-Nov-2005

02:45

x86

WOW

Wcatsrvut.dll

2001.12.4720.445

584,192

17-Nov-2005

02:45

x86

WOW

Wclbcatex.dll

2001.12.4720.445

98,304

17-Nov-2005

02:45

x86

WOW

Wclbcatq.dll

2001.12.4720.445

490,496

17-Nov-2005

02:45

x86

WOW

Wcolbact.dll

2001.12.4720.445

56,832

17-Nov-2005

02:45

x86

WOW

Wcomadmin.dll

2001.12.4720.445

189,440

17-Nov-2005

02:45

x86

WOW

Wcomsvcs.dll

2001.12.4720.445

1,209,344

17-Nov-2005

02:45

x86

WOW

Wes.dll

2001.12.4720.445

226,816

17-Nov-2005

02:45

x86

WOW

Wmsdtcprx.dll

2001.12.4720.445

445,952

17-Nov-2005

02:45

x86

WOW

Wmsdtcuiu.dll

2001.12.4720.445

160,768

17-Nov-2005

02:45

x86

WOW

Wmtxclu.dll

2001.12.4720.445

76,288

17-Nov-2005

02:45

x86

WOW

Wmtxdm.dll

2001.12.4720.445

18,944

17-Nov-2005

02:45

x86

WOW

Wmtxoci.dll

2001.12.4720.445

109,056

17-Nov-2005

02:45

x86

WOW

Wole32.dll

5.2.3790.445

1,193,984

17-Nov-2005

02:45

x86

WOW

Wolecli32.dll

5.2.3790.445

72,192

17-Nov-2005

02:45

x86

WOW

Wolecnv32.dll

5.2.3790.445

36,352

17-Nov-2005

02:45

x86

WOW

Wrpcproxy.dll

5.2.3790.141

26,112

17-Nov-2005

02:45

x86

WOW

Wrpcrt4.dll

5.2.3790.141

544,256

17-Nov-2005

02:45

x86

WOW

Wstclient.dll

2001.12.4720.445

60,416

17-Nov-2005

02:45

x86

WOW

Wtxflog.dll

2001.12.4720.445

95,232

17-Nov-2005

02:45

x86

WOW

Windows Server 2003 SP1, Itanium Architecture

File name

File version

File size

Date

Time

Platform

SP requirement

Service branch

Catsrv.dll

2001.12.4720.2572

657,408

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Catsrvut.dll

2001.12.4720.2572

1,632,256

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Clbcatex.dll

2001.12.4720.2572

279,040

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Clbcatq.dll

2001.12.4720.2572

1,353,728

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Colbact.dll

2001.12.4720.2572

181,760

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Comadmin.dll

2001.12.4720.2572

420,352

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Comrepl.dll

2001.12.4720.2572

285,184

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Comsvcs.dll

2001.12.4720.2572

3,366,912

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Comuid.dll

2001.12.4720.2572

1,977,856

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Es.dll

2001.12.4720.2572

701,440

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Msdtcprx.dll

2001.12.4720.2572

1,337,344

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Msdtctm.dll

2001.12.4720.2572

3,096,064

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Msdtcuiu.dll

2001.12.4720.2572

486,400

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Mtxclu.dll

2001.12.4720.2572

207,872

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Mtxdm.dll

2001.12.4720.2572

47,616

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Mtxoci.dll

2001.12.4720.2572

322,048

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Ole32.dll

5.2.3790.2572

3,999,744

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Olecli32.dll

5.2.3790.2572

252,416

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Olecnv32.dll

5.2.3790.2572

90,112

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Rpcss.dll

5.2.3790.2572

859,136

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Stclient.dll

2001.12.4720.2572

149,504

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Txflog.dll

2001.12.4720.2572

301,568

17-Nov-2005

02:45

IA-64

SP1

Not Applicable

Wcatsrv.dll

2001.12.4720.2572

273,920

17-Nov-2005

02:45

x86

SP1

WOW

Wcatsrvut.dll

2001.12.4720.2572

619,520

17-Nov-2005

02:45

x86

SP1

WOW

Wclbcatex.dll

2001.12.4720.2572

104,960

17-Nov-2005

02:45

x86

SP1

WOW

Wclbcatq.dll

2001.12.4720.2572

514,048

17-Nov-2005

02:45

x86

SP1

WOW

Wcolbact.dll

2001.12.4720.2572

58,880

17-Nov-2005

02:45

x86

SP1

WOW

Wcomadmin.dll

2001.12.4720.2572

196,608

17-Nov-2005

02:45

x86

SP1

WOW

Wcomsvcs.dll

2001.12.4720.2572

1,268,736

17-Nov-2005

02:45

x86

SP1

WOW

Wcomuid.dll

2001.12.4720.2572

596,480

17-Nov-2005

02:45

x86

SP1

WOW

Wes.dll

2001.12.4720.2572

238,592

17-Nov-2005

02:45

x86

SP1

WOW

Wmsdtcprx.dll

2001.12.4720.2572

470,528

17-Nov-2005

02:45

x86

SP1

WOW

Wmsdtcuiu.dll

2001.12.4720.2572

165,888

17-Nov-2005

02:45

x86

SP1

WOW

Wmtxclu.dll

2001.12.4720.2572

78,848

17-Nov-2005

02:45

x86

SP1

WOW

Wmtxdm.dll

2001.12.4720.2572

20,992

17-Nov-2005

02:45

x86

SP1

WOW

Wmtxoci.dll

2001.12.4720.2572

111,104

17-Nov-2005

02:45

x86

SP1

WOW

Wole32.dll

5.2.3790.2572

1,247,232

17-Nov-2005

02:45

x86

SP1

WOW

Wolecli32.dll

5.2.3790.2572

75,776

17-Nov-2005

02:45

Not Applicable

SP1

WOW

Wolecnv32.dll

5.2.3790.2572

38,912

17-Nov-2005

02:45

x86

SP1

WOW

Wstclient.dll

2001.12.4720.2572

64,000

17-Nov-2005

02:45

x86

SP1

WOW

Wtxflog.dll

2001.12.4720.2572

98,816

17-Nov-2005

02:45

x86

SP1

WOW

Windows Server 2003 SP1, x64

File name

File version

File size

Date

Time

Platform

SP requirement

Service branch

Catsrv.dll

2001.12.4720.2572

418,304

17-Nov-2005

02:45

x64

SP1

Not Applicable

Catsrvut.dll

2001.12.4720.2572

1,083,904

17-Nov-2005

02:45

x64

SP1

Not Applicable

Clbcatex.dll

2001.12.4720.2572

175,104

17-Nov-2005

02:45

x64

SP1

Not Applicable

Clbcatq.dll

2001.12.4720.2572

882,688

17-Nov-2005

02:45

x64

SP1

Not Applicable

Colbact.dll

2001.12.4720.2572

97,280

17-Nov-2005

02:45

x64

SP1

Not Applicable

Comadmin.dll

2001.12.4720.2572

288,768

17-Nov-2005

02:45

x64

SP1

Not Applicable

Comrepl.dll

2001.12.4720.2572

188,928

17-Nov-2005

02:45

x64

SP1

Not Applicable

Comsvcs.dll

2001.12.4720.2572

2,194,944

17-Nov-2005

02:45

x64

SP1

Not Applicable

Comuid.dll

2001.12.4720.2572

1,478,144

17-Nov-2005

02:45

x64

SP1

Not Applicable

Es.dll

2001.12.4720.2572

365,568

17-Nov-2005

02:45

x64

SP1

Not Applicable

Msdtcprx.dll

2001.12.4720.2572

830,464

17-Nov-2005

02:45

x64

SP1

Not Applicable

Msdtctm.dll

2001.12.4720.2572

2,073,088

17-Nov-2005

02:45

x64

SP1

Not Applicable

Msdtcuiu.dll

2001.12.4720.2572

291,328

17-Nov-2005

02:45

x64

SP1

Not Applicable

Mtxclu.dll

2001.12.4720.2572

144,896

17-Nov-2005

02:45

x64

SP1

Not Applicable

Mtxdm.dll

2001.12.4720.2572

30,208

17-Nov-2005

02:45

x64

SP1

Not Applicable

Mtxoci.dll

2001.12.4720.2572

175,104

17-Nov-2005

02:45

x64

SP1

Not Applicable

Ole32.dll

5.2.3790.2572

2,546,688

17-Nov-2005

02:45

x64

SP1

Not Applicable

Olecli32.dll

5.2.3790.2572

131,584

17-Nov-2005

02:45

x64

SP1

Not Applicable

Olecnv32.dll

5.2.3790.2572

56,832

17-Nov-2005

02:45

x64

SP1

Not Applicable

Rpcss.dll

5.2.3790.2572

698,368

17-Nov-2005

02:45

x64

SP1

Not Applicable

Stclient.dll

2001.12.4720.2572

101,888

17-Nov-2005

02:45

x64

SP1

Not Applicable

Txflog.dll

2001.12.4720.2572

180,224

17-Nov-2005

02:45

x64

SP1

Not Applicable

Wcatsrv.dll

2001.12.4720.2572

273,920

17-Nov-2005

02:45

x86

SP1

WOW

Wcatsrvut.dll

2001.12.4720.2572

619,520

17-Nov-2005

02:45

x86

SP1

WOW

Wclbcatex.dll

2001.12.4720.2572

104,960

17-Nov-2005

02:45

x86

SP1

WOW

Wclbcatq.dll

2001.12.4720.2572

514,048

17-Nov-2005

02:45

x86

SP1

WOW

Wcolbact.dll

2001.12.4720.2572

58,880

17-Nov-2005

02:45

x86

SP1

WOW

Wcomadmin.dll

2001.12.4720.2572

196,608

17-Nov-2005

02:45

x86

SP1

WOW

Wcomsvcs.dll

2001.12.4720.2572

1,268,736

17-Nov-2005

02:45

x86

SP1

WOW

Wcomuid.dll

2001.12.4720.2572

596,480

17-Nov-2005

02:45

x86

SP1

WOW

Wes.dll

2001.12.4720.2572

238,592

17-Nov-2005

02:45

x86

SP1

WOW

Wmsdtcprx.dll

2001.12.4720.2572

470,528

17-Nov-2005

02:45

x86

SP1

WOW

Wmsdtcuiu.dll

2001.12.4720.2572

165,888

17-Nov-2005

02:45

x86

SP1

WOW

Wmtxclu.dll

2001.12.4720.2572

78,848

17-Nov-2005

02:45

x86

SP1

WOW

Wmtxdm.dll

2001.12.4720.2572

20,992

17-Nov-2005

02:45

x86

SP1

WOW

Wmtxoci.dll

2001.12.4720.2572

111,104

17-Nov-2005

02:45

x86

SP1

WOW

Wole32.dll

5.2.3790.2572

1,247,232

17-Nov-2005

02:45

x86

SP1

WOW

Wolecli32.dll

5.2.3790.2572

75,776

17-Nov-2005

02:45

Not Applicable

SP1

WOW

Wolecnv32.dll

5.2.3790.2572

38,912

17-Nov-2005

02:45

x86

SP1

WOW

Wstclient.dll

2001.12.4720.2572

64,000

17-Nov-2005

02:45

x86

SP1

WOW

Wtxflog.dll

2001.12.4720.2572

98,816

17-Nov-2005

02:45

x86

SP1

WOW

Windows Server 2003, x86

File name

File version

File size

Date

Time

Catsrv.dll

2001.12.4720.445

258,560

17-Nov-2005

03:09

Catsrvut.dll

2001.12.4720.445

584,192

17-Nov-2005

03:09

Clbcatex.dll

2001.12.4720.445

98,304

17-Nov-2005

03:09

Clbcatq.dll

2001.12.4720.445

490,496

17-Nov-2005

03:09

Colbact.dll

2001.12.4720.445

56,832

17-Nov-2005

03:09

Comadmin.dll

2001.12.4720.445

189,440

17-Nov-2005

03:09

Comrepl.dll

2001.12.4720.445

86,528

17-Nov-2005

03:09

Comsvcs.dll

2001.12.4720.445

1,209,344

17-Nov-2005

03:09

Comuid.dll

2001.12.4720.445

565,248

17-Nov-2005

03:09

Es.dll

2001.12.4720.445

226,816

17-Nov-2005

03:09

Msdtcprx.dll

2001.12.4720.445

445,952

17-Nov-2005

03:09

Msdtctm.dll

2001.12.4720.445

965,120

17-Nov-2005

03:09

Msdtcuiu.dll

2001.12.4720.445

160,768

17-Nov-2005

03:09

Mtxclu.dll

2001.12.4720.445

76,288

17-Nov-2005

03:09

Mtxdm.dll

2001.12.4720.445

18,944

17-Nov-2005

03:09

Mtxoci.dll

2001.12.4720.445

109,056

17-Nov-2005

03:09

Ole32.dll

5.2.3790.445

1,193,984

17-Nov-2005

03:09

Olecli32.dll

5.2.3790.445

72,192

17-Nov-2005

03:09

Olecnv32.dll

5.2.3790.445

36,352

17-Nov-2005

03:09

Rpcproxy.dll

5.2.3790.141

26,112

16-Mar-2004

03:17

Rpcrt4.dll

5.2.3790.141

659,968

16-Mar-2004

03:17

Rpcss.dll

5.2.3790.445

296,960

17-Nov-2005

03:09

Stclient.dll

2001.12.4720.445

60,416

17-Nov-2005

03:09

Txflog.dll

2001.12.4720.445

95,232

17-Nov-2005

03:09

Windows Server 2003 SP1, x86

File name

File version

File size

Date

Time

Platform

SP requirement

Catsrv.dll

2001.12.4720.2572

273,920

17-Nov-2005

03:20

x86

SP1

Catsrvut.dll

2001.12.4720.2572

619,520

17-Nov-2005

03:20

x86

SP1

Clbcatex.dll

2001.12.4720.2572

104,960

17-Nov-2005

03:20

x86

SP1

Clbcatq.dll

2001.12.4720.2572

514,048

17-Nov-2005

03:20

x86

SP1

Colbact.dll

2001.12.4720.2572

58,880

17-Nov-2005

03:20

x86

SP1

Comadmin.dll

2001.12.4720.2572

196,608

17-Nov-2005

03:20

x86

SP1

Comrepl.dll

2001.12.4720.2572

88,576

17-Nov-2005

03:20

x86

SP1

Comsvcs.dll

2001.12.4720.2572

1,268,736

17-Nov-2005

03:20

x86

SP1

Comuid.dll

2001.12.4720.2572

596,480

17-Nov-2005

03:20

x86

SP1

Es.dll

2001.12.4720.2572

238,592

17-Nov-2005

03:20

x86

SP1

Msdtcprx.dll

2001.12.4720.2572

470,528

17-Nov-2005

03:20

x86

SP1

Msdtctm.dll

2001.12.4720.2572

1,009,664

17-Nov-2005

03:20

x86

SP1

Msdtcuiu.dll

2001.12.4720.2572

165,888

17-Nov-2005

03:20

x86

SP1

Mtxclu.dll

2001.12.4720.2572

78,848

17-Nov-2005

03:20

x86

SP1

Mtxdm.dll

2001.12.4720.2572

20,992

17-Nov-2005

03:20

x86

SP1

Mtxoci.dll

2001.12.4720.2572

111,104

17-Nov-2005

03:20

x86

SP1

Ole32.dll

5.2.3790.2572

1,247,232

17-Nov-2005

03:20

x86

SP1

Olecli32.dll

5.2.3790.2572

75,776

17-Nov-2005

03:20

Not Applicable

SP1

Olecnv32.dll

5.2.3790.2572

38,912

17-Nov-2005

03:20

x86

SP1

Rpcss.dll

5.2.3790.2572

421,888

17-Nov-2005

03:20

x86

SP1

Stclient.dll

2001.12.4720.2572

64,000

17-Nov-2005

03:20

x86

SP1

Txflog.dll

2001.12.4720.2572

98,816

17-Nov-2005

03:20

x86

SP1

Status

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section. This problem was first corrected in Windows Server 2003 Service Pack 2.

More Information

The DCOM 10009 event contains insufficient data about the underlying error that caused them to occur. Usually, the DCOM 10009 events are logged because of network communications failures with the DCOM server. These include problems such as name resolution issues and firewall issues. These issues frequently lead to 0x6ba (0x800706ba) RPC errors. To gather additional error information about the underlying error with this fix in Windows Server 2003, enable RPC Extended Error information (EEINFO). When EEINFO is enabled, additional data is written to the DCOM 10009 event data section of the event. In Windows Vista, you do not have to turn on EEINFO because it is on by default and will be dumped in the DCOM 10009 event data by default. EEinfo will typically contain winsock specific errors like 10048 (WSAEADDRINUSE) such as when all available TCP ports are exhausted.

For more information about RPC Extended Error information, including how to enable and how to interpret the information, visit the following Microsoft Developer Network (MSDN) Web site:

The following is an example of the event that is logged. It contains the additional useful data. In particular, the status, gencomp, and detloc information in the error data will be of interest. For example, the status 11001 is "No such host is known" and is generated by winsock (gencomp = 8).For more information, see Help and Support Center at the following Microsoft Web site:

The error that is mentioned in the "Symptoms" section is frequently a network communications error. The following are possible causes of this error:

Name resolution errors are occurring.

All TCP ports on the server are being used.

TCP port collisions are occurring.

To troubleshoot DCOM 10009 errors, use the following methods.

Method 1: Verify that name resolution is working correctly

The activation page for a COM+ proxy application contains a Remote Server Name (RSN) property. The RSN property can be an IP address, a Fully Qualified Domain Name (FQDN), or a NetBIOS name. To troubleshoot this issue, use the ping command to test connectivity to the remote server by using the IP address, the FQDN, and the NetBIOS name.

Method 2: Verify TCP port usage

When a client makes DCOM calls to a COM+ server application, each connection may use a different TCP port. Therefore, all TCP ports on the server may be used. When this condition occurs, the server cannot accept additional connections.

For more information about how to determine TCP port usage when you troubleshoot TCP/IP connectivity issues, click the following article numbers to view the articles in the Microsoft Knowledge Base: